Ya, not sure myself. I mean the action in my SB14 is really low and my fender is high so maybe that's why. Again, maybe it's just perceived tension and all in my head
There seem to be a number of factors. When playing with sufficiently loud amplification but with the treble rolled off strings feel subjectively looser to me. If there is a bit too much relief then the tension feels higher. I play with around a 1.5mm action at the E string and a 'standard' 2.4mm action seems like high tension, but it's actually fretting difficulty. A set of .105s with low action feel like lower tension that .100s with higher action, etc.